Rich wrote:

What is the best way to cut 6" cast iron sewage pipe?
Would a sawzall tackle this pipe or would an electric abrasive cutter be
better for the job?

Rent a "snap-cutter" for CI pipe.
If that's not practical for a one-time, I would go for the abrasive
saw blade. Depends if you can get the saw all the way around.
Sawzall works with a good blade *sometimes*. CI is quite variable;
some will cut like butter, others are extra hard and eats blades

Or....do like the old timers: gently make a groove all the way
around the pipe with a chisel, then break it apart:-)

If you use an abrasive saw, wear a good dust mask.

Jim